Hello, Running into an interesting problem - In short, I get an unexpected HDMI resync the first and ONLY first time playing content after a boot / reboot Details: Zidoo z2000 pro —> HD Fury VRROOM —> Yamaha A4A AVR —> Epson LS12000 Auto frame rate: frame rate only Resolution: 3840x2160p 23Hz 4k50-60: YUV420 10 bit 4k23-30 + non4k: YUV444 10 bit Deep Colour: Tried both HDMI signal format: Enhanced HDR: LLDV YUV444 12-bit I can reproduce this every time: - Turn on or reboot Zidoo - Play a movie that is 23.976 Hz Since resolution is set at 4k/23 and I have LLDV on I don’t expect any blip, but it happens every time. Observing the front display I can see HDR goes off for a second then comes right back on which causes a resync. Now, once this happens if I stop the movie and play again or try to play literally any other movie that is 23.976Hz it works fine with no resync whatsoever as I expect .75 fw btw All my cables are ultra high speed hdmi 2.1 certified
Can't think of any reason why it would do that and I certainly can't replicate here. Is the LLDV EDID in the Zidoo or the HDFury? Are you using LLDV YUV444 12-bit or do you mean 422 12-bit?
The LLDV EDID is all done on the hdfury side. You are right, my setting is LLDV YUV 422 12-bit, my bad. On the hdfury side I use “Automix” and check the DV box then use a custom DV data block for adjusting MaxLum
Hmm - possibly a problem with Automix - that uses the incoming EDID mixed with settings you define so it can be variable as devices boot. I can't think why that would cause a problem when the EDID is already stable but I would always use a custom EDID - it's more stable. Set the Automix EDID as normal, then hit "SAVE ACTIVE EDID TO CUSTOM EDID 10" Now activate Custom EDID and select #10 for the input you're using.
Thanks, I could give it a try. I am concerned I will lose the custom Dolby Vision block though. With automix I select CUSTOM for DV and then define that custom DV block under the DV tab that sets things like MaxLum. If I do custom EDID I am not sure there is a way to do that
That's what SAVE is for - you create an Automix EDID and when you hit SAVE, that EDID is saved to Custom 10. Then you just check CUSTOM, select EDID 10 for the input the Zidoo is connected to and bingo! You can't lose anything.
OK I went ahead and tried that. Just to confirm, before I changed anything I downloaded and decoded the existing EDID. Then, I saved the Automix EDID to custom8 and applied custom8 to the rx input connected to the zidoo, powered off and on the zidoo. Then, I downloaded and decoded the EDID again, and I could see I didn't lose my setting for Max Luminance Unfortunately, it didn't solve the problem. I still get a resync the first and ONLY the first time I play a move after bootup. The file doesn't matter. I've tried 1080p, 2160p files with 23.976 hz frame rate. It's really strange because after that first try it works flawlessly and never resyncs for anything that is 23.976. It's only the first time after boot. I do not recall ever seeing this before I introduced the hdfury so I wouldn't be surprised if that has something to do with it, but nevertheless I would love to figure out how to prevent it.
Weirder and weirder... Another thing to try is load the EDID into the Zidoo which will override the HDFury EDID and see if that solves it - just as a test to figure out where the problem is. The other suggestion is a factory reset.
Did a little testing today. If I change my HDR settings from LLDV 422 12-bit to VS10 hdr the problem goes away. Of course, I want to use LLDV though. Hmmmmm, another data point though.
I figured it out! If I have “Backlight Ctrl” enabled in the custom DV data block on hdfury, the problem occurs. If I disable that option, it works perfectly! I’m not sure if backlight ctrl is necessary to set “Backlight MinLum” on hdfury. I had mine set to 25 nits. I still see that in the EDID
Thanks! It was just a tedious process of elimination after seeing that the baked in “custom 10” profile on hdfury did NOT exhibit the problem I will be curious to see your results too. I wonder why Zidoo doesn’t like backlight ctrl
Damn -'I'll be honest, I completely forgot about this.. I'm on holiday at the moment but I'll send myself an email to check when I get back.
Ok, finally got around to trying this... Firstly - backlight control is a setting for compatible Dolby Vision displays that are able to modulate their backlight so is irrelevant if using LLDV for non-Dolby Vision displays. Secondly - sorry, but I can't replicate this. I changed backlight control from "Not Supported" to "Supported" and changed "Backlight Minimum" to 25 nits to match your settings. I checked the captured DV metadata from the source and it was transmitting backlight data which means the switch worked. But whatever I do I can't get HDMI to resync on first playback after rebooting or restarting the box. However, I've since found a problem with the BPD boxes and LLDV which might have some bearing on this. If I use the LLDV trick with my Samsung display and set 4K23 etc, I get no resyncs as you'd expect as long as the framerate doesn't change. However, on my JVC projector, bizarrely I get resyncs from LLDV GUI to LLDV playback - but unlike you, it happens every time (Of course the Z9X 1619DR box I use day to day in there doesn't do this!). I don't know if this is new behaviour because I don't use a BPD box in there, but I suspect it might be as there have been several firmware regressions lately and I haven't seen it before on the odd occasion I tested a BPD box in there. So I wonder if this is a similar issue to the one you're seeing. As I said above - weirder and weirder.... but if disabling backlight control works, then great! As I say, it doesn't do anything for you.
Thanks for spending the time testing thoroughly. As far as this issue, I have not had any problems since toggling off backlight control
